Health monitoring system

• US 6,282,441 B1
• Filed: 11/23/1999
• Issued: 08/28/2001
• Est. Priority Date: 02/24/1995
• Status: Expired due to Term

• Current Assignee: Brigham and Women's Hospital Incorporated
• Original Assignee: Brigham and Women's Hospital Incorporated
• Inventors: Singer, Daniel B., Raymond, Stephen A., Gordon, Geoffrey E.
• Primary Examiner(s): Getzow, Scott M.
• Application Number:
  US09/447,986
• Time in Patent Office: 644 Days
• Field of Search: 600/509, 600/513
• US Class Current: 600/513
• CPC Class Codes: A61B 2560/0209 adapted for power saving
• CPC Class Codes: A61B 2560/0242 adapted to measure environmental factors, e.g. temperature, pollution
• CPC Class Codes: A61B 2560/0257 using atmospheric pressure
• CPC Class Codes: A61B 2560/0295 adapted for recording user messages or annotations
• CPC Class Codes: A61B 5/002 Monitoring the patient using a local or closed circuit, e.g. in a room or building A61B5/0017 takes precedence
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/02055 Simultaneously evaluating both cardiovascular condition and temperature
• CPC Class Codes: A61B 5/02405 Determining heart rate variability
• CPC Class Codes: A61B 5/1135 by monitoring thoracic expansion
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/33 specially adapted for cooperation with other devices
• CPC Class Codes: A61B 5/332 Portable devices specially adapted therefor
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/366 Detecting abnormal QRS complex, e.g. widening
• CPC Class Codes: A61B 5/4824 Touch or pain perception evaluation A61B5/4821 takes precedence
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61B 5/6831 Straps, bands or harnesses
• CPC Class Codes: A61B 5/6861 Capsules, e.g. for swallowing or implanting
• CPC Class Codes: A61B 5/7232 involving compression of the physiological signal, e.g. to extend the signal recording period
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61B 5/7435 : Displaying user selection data, e.g. icons in a graphical user interface
• CPC Class Codes: A61B 5/7475 : User input or interface means, e.g. keyboard, pointing device, joystick
• CPC Class Codes: A61B 7/00 : Instruments for auscultation
• CPC Class Codes: A61M 31/002 : Devices for releasing a drug at a continuous and controlled rate for a prolonged period of time artificial gland structures or devices A61F2/022; intra-uterine contraceptive devices A61F6/14; tampons for introducing into the vagina A61F13/20, A61L15/00; suppositories or bougies for intra-vaginal or intra-uterine application A61K9/02; physical forms of medicinal preparations for sustained or differential drug release A61K9/20, A61K9/50
• CPC Class Codes: G16H 10/60 : for patient-specific data, e.g. for electronic patient records
• CPC Class Codes: G16H 40/67 : for remote operation

Abstract

A health monitoring system which tracks the state of health of a patient and compiles a chronological health history of the patient uses a multiparametric monitor which periodically and automatically measures and records a plurality of physiological data from sensors in contact with the patient'"'"'s body. The data collected is not specifically related to a particular medical condition but, instead, provides the information necessary to derive patterns which are characteristic of healthy patients as well as those who are ill. The data collected is periodically uploaded to a database in which it is stored along with similar health histories for other patients. The monitor is preferably self-contained in a chest strap which is located on the patient'"'"'s torso, and makes use of a controller which controls sampling of the desired data and storage of the data to a local memory device pending uploading to the database. The more voluminous data collected is reduced and compressed prior to storage in the local memory device. Preferably, much of the monitor circuitry is run intermittently to conserve power. The monitor data is supplemented with subjective data (such as psychological and environmental conditions) collected from the patient using a handheld data input device which runs a program to solicit information from the patient. The subjective data collected is chronologically aligned with the monitor data in the database such that the health history of a patient includes both objective and subjective medical data.

Claims

1. A personal health monitor comprising:

a portable, physiological monitoring device which periodically and automatically measures and records from a subject physiological data comprising electro-cardiogram (EKG) data descriptive of an EKG signal;

a time base which tracks the time of recording of the physiological data; and

a data storage unit in which the physiological data is stored with reference to the time base, the EKG data including data representative of temporal intervals between occurrences of relevant features of a repeating EKG waveform for each heartbeat, the stored data including interval differences indicative of a difference between the duration of one of said intervals and the duration of a later of said intervals.

2. A personal health monitor according to claim 1 wherein said intervals include a heartbeat interval between a characteristic feature of an EKG waveform for one heartbeat and a corresponding characteristic feature of an EKG waveform for a second heartbeat.

3. A personal health monitor according to claim 2 wherein the heartbeat interval comprises an interval between a point of maximum slope of the EKG waveform for one heartbeat during the first heartbeat and a point of maximum slope of the EKG waveform for one heartbeat during the subsequent heartbeat.

4. A personal health monitor according to claim 1 wherein said intervals include a first feature interval between a starting point of a first feature of an EKG waveform for one heartbeat and an ending point of said first feature, and a second feature interval between a starting point of a second feature of an EKG waveform for a second heartbeat that corresponds to the waveform feature of the first heartbeat and an ending point of the second feature interval of the second heartbeat, and wherein said interval differences include data indicative of a difference between the length of the first feature interval and the second feature interval.

5. A personal health monitor according to claim 1 wherein, when a measured interval difference exceeds a predetermined length, a time reference is recorded that is indicative of when that interval occurred in time.

6. A personal health monitor according to claim 1 wherein the EKG data being stored comprise indicia of a relative slope of the EKG waveform for one heartbeat.

7. A personal health monitor according to claim 6 wherein the EKG data recorded comprise data indicative of a point of steepest relative slope for at least one predetermined feature of the EKG waveform for each heartbeat.

8. A personal health monitor according to claim 6 wherein data regarding a waveform feature of the EKG waveform for one heartbeat is recorded as data indicative of a relative slope of the feature and a point in time of the feature.

9. A personal health monitor according to claim 8 wherein said point in time of the segment is a point in time at which a point of median magnitude of the segment occurred.

10. A personal health monitor according to claim 1 wherein a duration of a segment of an EKG waveform for one heartbeat is determined by sampling the EKG signal periodically and determining the number of samples taken between a first sample that exceeds a first predetermined threshold and a second sample that exceeds a second predetermined threshold.

11. A personal health monitor according to claim 10 wherein said duration is measured for at least one of the following features:

upslope, downslope and recovery slope segments of the EKG waveform for one heartbeat.

12. A personal health monitor according to claim 1 wherein, for each EKG waveform for one heartbeat, maximum and minimum values are determined and used for subsequent interval determinations.

13. A personal health monitor comprising:

a portable, physiological monitoring device which periodically and automatically measures and records from a subject physiological data comprising electro-cardiogram (EKG) data descriptive of an EKG signal;

a time base which tracks the time of recording of the physiological data; and

a data storage unit in which the physiological data is stored with reference to the time base, wherein the EKG signal comprises an EKG waveform for one heartbeat, and the stored data includes data indicative of a waveform structure of a key segment of the EKG signal, wherein the data indicative of the key segment includes data indicative of a point in time at which a magnitude of the EKG signal crossed a first predetermined threshold and a point in time at which the signal magnitude crossed a second predetermined threshold.

14. A personal health monitor according to claim 13 wherein said point in time of the key segment is a point in time at which a point of median magnitude of the first segment occurred.

15. A personal health monitor according to claim 13 wherein periodic samples of the EKG signal are taken to record the EKG waveform for one heartbeat, and the key segment for each is determined to begin at a point in time corresponding to a first sample that exceeds the first threshold, and is determined to end at a point in time corresponding to a second sample that exceeds the second threshold, and wherein the number of samples between the first and second samples is indicative of the slope of the key segment.

16. A personal health monitor according to claim 15 wherein maximum and minimum values of the EKG waveform for one heartbeat are determined and used to calculate said thresholds when the first segment is part of a subsequent heartbeat pattern.

17. A personal health monitor according to claim 16 wherein maximum and minimum values of the EKG waveform for one heartbeat are determined and used to calculate said thresholds when the key segment is part of a subsequent EKG waveform for one heartbeat.

18. A personal health monitor comprising:

a portable, physiological monitoring device which periodically and automatically measures and records from a subject physiological data comprising electro-cardiogram (EKG) data descriptive of an EKG signal;

a time base which tracks the time of recording of the physiological data; and

a data storage unit in which the physiological data is stored with reference to the time base, wherein the EKG signal comprises a repeating EKG waveform for one heartbeat, and the stored data includes a timestamp for each EKG waveform for one heartbeat, each timestamp corresponding to a point of steepest relative slope of a predetermined segment of each EKG waveform for one heartbeat.

19. A personal health monitor according to claim 18 wherein at least one of said segments is determined by sampling the EKG signal periodically and determining a number of samples taken between a first sample that exceeds a first predetermined threshold and a second sample that exceeds a second predetermined threshold.

20. A personal health monitor according to claim 19 wherein a timestamp in a given segment is located at a point of substantially median magnitude between the first predetermined threshold and the second predetermined threshold for that segment.